Sun Microsystems Fire 880, Руководство пользователя

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74 Sun Fire 880 Server Owner’s Guide • August 2001
The system can accommodate a maximum of three power supplies, each with its
own 20-amp AC power cord. Each power supply is auto-ranging, providing up to
1120 watts of DC power at 120/240 VAC line input. The basic system configuration
comes with two power supplies installed, which together provide sufficient power
for a maximally configured system. You can add an optional third power supply to
provide N+1 power redundancy, allowing the system to continue operating should
any one of the power supplies fail.
Each power supply provides a total of five DC output voltages (3.3V, 5.0V, 12V, 48V,
and 5.0V standby). Output current is shared equally between each of the supplies
via active current sharing circuitry.
Power supplies in a redundant configuration feature a hot-swap capability. You can
remove and replace a faulty power supply without shutting down the operating
system or turning off the system power. For additional details, see “About
Hot-Pluggable and Hot-Swappable Components” on page 144.
Each power supply has three status LEDs to provide power and fault status
information. For additional details, see “About Power Supply LEDs” on page 163.
Configuration Rules
■
Sun Microsystems recommends that you connect each power supply to a
dedicated AC circuit. Consult your local electrical codes for any additional
requirements.
■
The minimum system configuration requires two power supplies. Systems
configured with only one power supply are not supported.
■
A system configured with two power supplies may shut down abruptly if either
power supply fails. Installation of an optional third power supply enables the
system to remain fully operational should any one of the power supplies fail.
■
Power supply bays 0 and 1 must always contain power supplies. If a power
supply in either bay fails and the system can continue to operate, you must leave
the failed power supply in its bay until you are able to install a functioning
replacement power supply. A failed power supply in bay 0 or 1 still acts as an air
baffle, channeling airflow to cool the bottom row of disk drives in the disk cage.
The failed power supply should be replaced as soon as possible to regain N+1
power redundancy.
Caution –
If any power supply fails, leave the supply in its bay until you are ready
to install a replacement.
For information about installing power supplies, see “How to Install a Power
Supply” on page 39.